Due to thin film transistor liquid crystal displays (TFT-LCD) having advantages of high colorfulness, less volume, and low power consumption, they are dominant in current flat panel displays. As one important component of the liquid crystal display, a color filter filters light mainly through RGB color layer to achieve color. The RGB color layer of conventional TFT-LCD is mainly formed through exposure and development by utilizing yellow light lithography, there are problems of complex processes and longer time consumption; the color photoresist layer has lower backlight utilization; and due to limitation of the material itself, brightness and color saturation of the display is hard to obtain a greater enhancement.
Quantum Dots (QDs) refer to semiconductor crystal particles of diameters in 1-100 nm. Due to the less diameter of QDs, less than or close to exciton Bohr radius of corresponding bulk material produces quantum confinement effect, continuous band structure of the bulk material will be converted into discrete energy level structure, and electrons transition and fluorescence emission will occur in excitation of external light. Such special discrete energy level structure of QDs allows half wave width thereof being narrower, so they can emit monochrome light of higher purity, and have higher luminous efficiency compared with the conventional displays. Simultaneously, since sizes of QDs affects band gap of their energy levels, light of various wavelengths can be excited to emit by adjusting the dimensions of QDs or using QDs of different ingredients. In order to meet demands of people requiring display of high color saturation and wide color gamut, to add photoluminescence quantum dot device in backlight structures become an effective selection for major display manufacturers.
Additionally, the electrode material of indium tin oxide (ITO), which is extensively used in TFT-LCD, is currently faced with trends of fewer resource and increasing price; and ITO is flexure intolerance, it cannot meet curved surface design of panel, the characteristics of the material itself restricts to further thin or lighten the panel.
Graphene is a novel carbon nanomaterial, which is a monolayer network structure composed of carbon molecules, and has characteristics of good electron conductivity, low impedance, high transmittance, fine chemical stability, excellent mechanical performance. Raw material graphite for preparing the graphene have wide sources and cheap prices, and the graphene can undergo simple screen flexure or curved surface design, these excellent characteristics allow the graphene become a mainstream material for replacing ITO.